番石榴，俗稱芭樂，含有豐富蛋白質、維生素A、維生素C等營養物質及鈣、磷、鎂等微量元素，是非常好的熱帶水果，芭樂葉泡茶在民間也常被當作降血糖、解渴的飲品。本實驗將甲醇萃取芭樂葉以水回溶後，先後以正己烷、乙酸乙酯、正丁醇進行分層萃取，最後合計取得正己烷、乙酸乙酯、丁醇及水層等四種萃取物，我們檢測到芭樂葉四個分層以水層之細胞毒性最低，已知水層在動物實驗中具有降血糖作用，我們因此想進一步觀察水層對於脂肪細胞是否有幫助吸收糖分的作用。並因3T3-L1屬於纖維母細胞，需先分化後才會對胰島素的刺激有反應，在降低FBS的濃度後，最佳的3T3-L1細胞分化條件為DMⅠ(differentiation medium Ⅰ)刺激四天後，以DMⅡ(differentiation medium Ⅱ)刺激六天，並進行初步葡萄糖攝入實驗，發現0.1 mg/mL的水層萃取物可以幫助細胞攝取葡萄糖。
Psidium guajava, commonly known as guava, is rich in protein, vitamin A, vitamin C, calcium, phosphorus, magnesium and other trace elements, is a very delicious tropical fruit. Guava leaf tea has been used as a hypoglycemic drink as well as a thirst quencher. The guava leaf was extracted with methanol and further partitioned as hexane, ethyl acetate, butanol and aqueous partitions. We set out to examine the cytotoxicity associated with each partition of the guava leaf extract. The aqueous partition is the least cytotoxic partition when compared to other partitions. Previous studies have confirmed that guava leaf extract has a hypoglycemic effect in animal experiments. We would like to know whether the aqueous partition of the guava leaf extract may stimulate glucose uptake in adipocytes. However, 3T3-L1 need to be differentiated before they would respond to insulin stimulation, so we need to optimize 3T3-L1 cell differentiation process before conducting such experiments. We chose to lower fetal bovine serum (FBS) concentration as a starting point of inducing 3T3-L1 cell differentiation, after incubated in differentiation medium (DM)Ⅰfor four days and differentiation mediumⅡfor six days. Glucose uptake test found that 0.1 mg/mL aqueous extract can enhance glucose uptake in adipocytes.
